Transformer for electric vehicles.



No, 876,988. PATENTED JAN. 21, 1908. W. s. MOODY.

TRANSFORMER FOR ELECTRIC VEHICLES.

APPLICATION FILED AUG. 10. '1904.

3 SHEETS-SHEET 1.

ix u Fig! Witnesses:

mvewizon WUULeP v'ssziy W EV PATENTED JAN. 21, 1908.

W. S. MOODY. TRANSFORMER POE ELECTRIC VEHICLES.

APPLICATION FILED AUG.10, 1904.

3 SHEETS-SHEET 2.

i nventon I Waier S. dy.

PATENTED JAN. 21, 1908. W. S. MOODY.

TRANSFORMER FOR ELECTRIC VEHICLES.

APPLIOATION FILED AUG. 10, 1904 3 $HBETSSHBET 3. F :q. 6.

inventar, 7 Walter S.Moody.

the heat UNITED srnrns WALTER- S. MOODY,

OF SOHENEOTADY, NEW YORK, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

TRANSFORMER FOR ELEGTRIEC VEHICLES.

Speeification'of Letters Patent.

Patented Jan. 21, 1908.

To all whom it may concern:

Be. it known that I, (VALTER S. Moonr, a citizen of the United States, residing at Schenectady, county of Schenectady, State of New York, have invented certain new and useful Improvements in Transformers for Electric Vehicles, of which the following is a specification.

It is sometimes desirable to supply alternating current at one potential from stationary supply conductors to one windingof a transformer located on a movable vehicle, the other winding of the transformer furnishing alternating current of different potential to consuming devices located on or traveling with the vehicle. the motors which propel electric railway .cars may be driven by alternating current furnished to the low-pressure winding of a transformer carried by the car, the high pressure winding of which is supplied with alternating current through stationary conductors and traveling contacts. In such a case the transformer used is subjected to somewhat violent mechanical vibrations, particularly when the car is operated at high speed. This necessitates very careful construction, particularly when, as may be the case, the'transformer is located beneath the car body.

One of the objects of my present inven tion is the construction of a transformer which, while compact and of comparatively light weight, is well adapted to stand rough usage such as may be experienced when the transformer is used on a traveling vehicle as above mentioned.

Another object ofsmy invention is to so construct and arrange a transformer that generated init may be rapidly (lissipated without producing an undue rise in the temperature of the transformer.

I accomplish the last object of my invention artly by providing my transformer with large and efiicient heat-radiating surfaces, and partly through a construction by means of which the movement of the car generate air currents which engage the transformer to cool it.

The various features of novelty which characterize my invention are pointed out with articnlarity in the claims annexed to and orming a part of this specification. Fora better understanding of myinvention, however, reference may be. hadv to the am For instance,

companying drawings and description in which I have illustrated and described one embodiment ofmy inventionf Of the drawings, Figure l is an elevation of an electric car equipped with my invention,

rangement of the conduit sectional elevation showing the hood at one may be employed;

diagrammatic view showing an arrangement of the transformer, air compressor, and air reservoir.

Referring to the drawings, 1 represents a car of the ordinary type employed on high speed interurban electric railways. poles 2 located at each end of the car are alternately employed to take alternating current from an overhead conductor 3 at comparatively high potential, say 2,000 volts, and deliver it to the primary winding of a transformer 4 located below the car body. The secondary of the transformer supplies current at a reduced potential, say 400 volts, to suitable motors mounted on the trucks 5. The return conductor of the primary system includes the wheels 6 and rails 7.

The core of the transformer, which is sub stantially of the type shown by the patent to Hall, No. 755,766, granted March 29, 1904, comprises a central elongated horizontal leg or portion 8 and four legs or branches 9 which are similar to each other and are spaced equally about the leg 8 and extend tend radially from each end of the leg or branch 8 to the ends of the legs or branches 9. The windings of the transformer surround the central leg 8 and are located in the space between the lcgs 9 and end portions 10.

Each outer leg 9, corresponding end pontions 10, and a quarter of the central leg or portion 8 of the core, are formed by two undies 11 and 12 of laminae of magnetic material. The bundles 1 1 are similar to the bundles 12 in that they are both rectangular in outline and formed with rectangular openl fags passing through them. The bundles broken awayand in section; and Fig. 9 is a Fig. 2 is a sectional elevation showing the ar- 4 Fig. 3 is a partial end of the conduit; Fig. 4 isan elevation showing the removable Trolley parallel therewith, and portions 10 which eX- differ from each other, however, in the fact I is also in the form of a copper strip or ribbon that the inner legs of the bundles 11 are substantially twice as wide as the corresponding legs of the bundles 12. The inner portions of the four pairs of bundles 11 and 12 form: ing the core are assembled together as shown to form the central leg or branch 8 which is cruciform in cross-section.

Angle bars or plates 13 are placed in the notched corners of the cruciform-shaped central leg or core 8 with their outer surfaces bearing against the sides ofthe laminm. The inner legs of each pair of bundles 11 and 12 are clamped together by bolts 14 which ass transversely through the bundles 11 an 12 and the adjacent flanges of the angle bars 13.

As is clearly shown in the drawings, a cross shaped ventilating space 14 extends through central leg or separatedby spacers 15 for this urpose.

Each outer'leg'9, which is su stantially rectangular in cross-section, is shown as somewhat wider in a direction measured perpendicular to the plane of lamination than is the central leg 8. This result is obtained by interleaving with the laminae in the legs 9 corresponding to those in the inner legs or branch 8, thelaminae being sides of the bundles 11 and 12 additional laminae. ConveXly curved members 16, which may be formed of cast iron or the like, are located between adjacent sides of the ad jacent core legs 9. The members 16 are formed witlrfaces or surfaces at right angles to each other, which abut against the sides of the adjacent core legs. The outer edges of these faces are flush with the outer edges of the core legs. The members 16 are formed with lugs 17 which are located adjacent to and roject beyond the outer surface of the'core egs. Bolts 18 passing through apertures formed in' the lugs 17 are employed to clamp each core leg between theadjacent members 16. As shown, the bolts 18 are located beyond the outer surface ofthe corresponding inner surface core leg 9. The members 16 are formed on their outer surfaces with heat-dissipating ribs 16 which extend parallel to the length of the transformer and the line of motion of the car. I

End plates or head members 20 are clamped against the ends of the core and the ends of the members 16 by bolts 21. The bolts 21 pass through and are positioned by apertured ugs 23 projecting for the purpose from the of the members 16. To stiffen the construction, members 25 pivoted on the bolts 21 have formed in them threaded apertures in which are located bolts 26, the ends of which are forced against the angle bars 13.

The windings of the transformers comprise two concentric sections and 31. The inner section 30 in turn-comprises an inner primary coil 32 preferably formed out of a cop edgewise to form a helix, and an outer secondary coil 33 which preferably of insulating material 37 and may bent edgewise into a helix. A layer 31 of insulating material is placed between the coils 31. and 32 which may be taped together.

The outer section 31 is formed of an inner I secondary coil which is substantially similar to the coil 33 and an outer primary coil 36 which is substantially similar to the coil The coils 35 and36 are separated by a layer be taped The sec- 5 together as are the coils 32 and 33.

tions 30 and 31 are separated from each other to form a ventilating space by separators or space blocks 38.

i The coils, which themselves possess consid- 8Q erable mechanical strength by reason of their construction, are locked tightly in place between the central leg Sof the core and the outer leg 9 by strips or spacers 40 of insulating material. After' the coils are firmly locked in place by the spacers 40 the coils and core are several times dipped in a heavy insulating compound or paint toseal the core, thespacing strips and the coils into a rigid mechanical structure. The exteriorof the shell formed by the legs ,9 and members 16 is made water-tight by a coating of water-proof paint or the like.

The transformer is placed beneath the car body with the legs 8 and 9 extending parallel to the direction of movement of the car and is supported by a skeleton frame or cradle 41 comprising a number of substantially U- shaped wrought iron bars 42 which are connected at their upper ends by rails 43. Notches are formed in the lugs 17 to receive and'position the U-shaped members 42. Bolts passing through the U-shaped bars 42 and rails 43 are employed to secure the cradle to the car structure.

As is clearly shown in the drawings, the end plates of the transformer are formed each with a cylindrical flange or lip 45 which surrounds an opening 46 centrally located in the end plate. To stiffen the structure a 11( number of bars 47. extend transversely across the openings 46. Conduits 48, the bodies of which are located between the floor-beams 48 of the car, extend from points adjacent the ends'of the'transformer to points adje: 11b

cent the ends of the car. A pipe or conduit section 49 is employed to connect each end of the transformer-to the adjacent end of the corresponding conduit. The conduit section 49 may be hinged to the conduit body as shown at 49 and provided with a collar 50 which may be locked removably about the flange 15 by thumbscrews 51 as shown in Fig. 5. A hood or funnel 52- is connected to the outer end of each conduit. it will be adily 1, :1: understood that the movement the will cause air'to be taken imby the forward funnel and delivered through the forward conduit 48 and section a to the interior of the transformer from which itwill escape 1;:

through the rear section 4-9, conduit 48, and funnel 52. The passage of air through the transformer will, of course, remove h at generated in the transformer. 5 To prevent the entrance of dirtinto the transformer a screen 53 is placed at the mouth of each funnel; Traps 5+1 (see Fig. ll

are preferably provided in the conduits at each side of the transformer, into which the bulk ofthe dirt passing the corresponding screens is collected. The traps 54 also serve to prevent rain and snowfrom entering the transformer. By making the conduit sections 49 removable as described, the interior of the transformer can lie-readily cleaned of any dirt which may accumulate in it by the use of a compressed air cleaning device.

As shown diagrammatically in Fig. l) of the. drawings, I may connect the intake/pipe 56 of the air compressor 57, which fills the reservoir with air for the operation of the car brakes, to take air from the interior of the transformer. The pipe 56 may be connected to the middle of the upper cover plates 55 by connections 55 as shown. This increases the an circulation through the transformer in an advantageous manner as the brakes are used most frequently and consequently the air pumped most rapidly by 3i) the compressor when the car is running at comparatively low speed and when therefore the circulation produced by the motionot the car proper is least noticeable.

The transformer consl ruciion which I have hereili described and illustratml in detail possesses many advantageous features of construction and -arrangemenl which are not limited to use for any particular purpose or in any particular arrangement. The construction, however, embodies features which are particularly useful when the transformer is to be mounted bencaih a car as shown in Fig. l. The design. is one in which the length of the ransl'ormcr may be made com- '45 paratively great with reference to the other dimensions of the iransformen This is of 'importance in view of the limited space in which the transformer mus-1 be snpporlmi.

It is frequently dcsiraulolo ma kc a transformer air-cooled rather than oil-cooled lo economize space by dispensing with the oilcontaining casing or forolhel' reasons. Willi the constructionshown, an z\il -oolc(l iransformer is obtained in which i'he windings are 5 thoroughly protected and im'nsed while at the same time the casing employed is such as to leave a very largc'porlion of lhe ('orc s :r

face exposed to the outside air, thus facilitating heat rmliation. As shown, the upper 6 and lower legs 9 of the corresponding end portions 10 and portion of leg 8 are lamil nated in vertical planes, while the ngnminder of the core is laminated in horizontal planes.

, It will thus be observed that all the electrical and magnetic advantages to be. obtained by l placed, a return accnl branches of said return circuit.

322,016, filed June 16, 1906.

What I claim as new, and desire tosecure by Letters Patent of the United States, is,

1. In combination, a transformer core com prising a central leg or branch, awinding placedabout said central le or branch, are turn magnetic circuit for said leg or branch comprising a number of legs arranged about the central leg and winding, and covers for the winding secured between adjacent branches of said returncircuit;

2. In combination, a transformer core 90 comprising a central leg or branch, aw'inding placed about said. central leg or branch, a return magnetic circuit for said leg orbranch' comprising a number of legs arranged about the central leg and Winding, and covers for the winding secured between adjacent branches of said return circuit, said covers being provided withheat-radiating ribs,

3. In a transformer havinga core and a winding, a casing surrounding said winding 100 formed of alternating core portions and co vcr members.

4. In a transformer having a core and a winding, a casing surrounding said winding formed of alternating core portions and cover members, said cover members being provided with heat-radiating ribs.

5. A transformer core, comprising a central leg or branch about which. windings are circuit for said leg or branch comprising a number of lcgs'parallel to the lirst-mentioncd leg and arranged :bout the iirst-mcntimied leg, and cover plates for the windings located between ad- (3. In a transformer, a core comprising laminated portions separated from each other by splices, and cover members connecting adjacent core portions to form a casing.

7. in a. lranslormer, a central leg or branch of magnetic material, windings surrounding said central branch, and a return circuit for said central branch formed of a number of parts which are arranged about said central leg or branch, each of said parts being formedof laminated material, some of said parts being laminated in different planes from other of said parts, each of said parts being connected with adjacent parts by a supp0rting member, thesupporting members and parts being secured together to form a shell surrounding said windings.

8. In a transformer, a central member about which windings are placed, and a di vided magnetic return circuit therefor commeans for securing saidparts together in a rigid. structure without impeding the circula-.

tion of a cooling fluid against the outer surfaces of said parts.

9. In combination, a movable vehicle and a transformer carried thereby, said transformer comprising a core, a winding, and a casing surrounding said winding formed of alternate core portions and cover members, said cover members being provided with heat radiating ribs extendi tion of the Vehicle.

ng parallel to the moparallel to thelegs.

11. In a transformer, a core comprising laminated portions separated from each ing adjacent core portions to form a casing, said cover members being provided with heat radiating ribs.

- In witness whereof Ihave hereunto set my hand this 5th day of August, '1904.

XVALTER S. MOODY.

Witnesses 2 BENJAMIN B. HULL, HELEN ORFORD.

10. A transformer core comprising a cen cuit, said cover plates being provided with heat radiating ribs or projections extending other by spaces, and cover members engag- 

